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A two-parameter high-pressure equation of state (EOS) is derived on the basis of the lattice potential theory using the concept of a short-range force constant as introduced by Born and Huang. The application of the EOS to some solids is presented and compared with the Birch-Murnaghan (BM) third-order EOS, the BM fourth-order EOS, and the Vinet EOS. A comparison of the results provides a crucial test for the EOSs used in this article. [ABSTRACT FROM AUTHOR]

The properties of neutron stars are investigated by including δ meson field in the modified quark-meson coupling model. It is found that δ meson has opposite effects on hadronic matter with or without hyperons: it softens the EOSs of hadronic matter with hyperons, while it stiffens the EOSs of pure nucleonic matter. Moreover, by replacing the isovector mesons with the contact scalar-isovector interaction, a considerable change of proton fraction is observed. It is shown that the contact scalar-isovector interaction provides an approach to satisfy the constraint of Direct Urca critical star masses. However, the inclusion of δ meson increases the proton fraction, consequently it decreases the MDU which departs farther from the Direct Urca constraint. Furthermore, the inclusion of δ meson field can increase the maximum mass of neutron star and enlarge the corresponding radius, while these quantities are decreased when the contact scalar-isovector interaction is included. [ABSTRACT FROM AUTHOR]

We have extended the complex scaled Green's function method to the relativistic framework describing deformed nuclei with the theoretical formalism presented in detail. We have checked the applicability and validity of the present formalism for exploration of the resonances in deformed nuclei. Furthermore, we have studied the dependences of resonances on nuclear deformations and the shape of potential, which are helpful to recognize the evolution of resonant levels from stable nuclei to exotic nuclei with axially quadruple deformations. [ABSTRACT FROM AUTHOR]

In order to realize intelligence management of guide sign system, this paper proposed an algorithm for deploying guide signs using guide sign data model from the perspective of road guiding levels. The algorithm took road intersection as research object, and guide sign information was classified into two categories, namely, connection signs and direction signs according to the relationship of guide signs information and road network topology. Moreover, the paper illustrated the selection principles of directional signs based on road guiding levels, and constructed deployment algorithm model for directional signs. Finally, a case study was conducted: the deployment model was tested in Guangzhou Higher Education Mega Center. The result revealed that the data model could support the automatic deployment, analysis and evaluation for guide signs. [ABSTRACT FROM AUTHOR]

We applied the complex scaling method to study the resonances of a Dirac particle in the Yukawa potential, and obtained the corresponding energies and widths. In the non-relativistic limit, our results are in excellent agreement with those by non-relativistic calculations with J-matrix approach. Furthermore, we found that the energies and widths of spin doublets are approximately degenerate, and preserve a good spin symmetry. The quality of spin symmetry is correlated with the parameters of the Yukawa potential. [ABSTRACT FROM AUTHOR]

Due to the complex structures associated with neutron resonance cross sections, their accurate evaluation has received considerable attention in the field of nuclear data research. The traditional R-matrix method still faces some difficulties in evaluating the neutron resonance data, especially in briefly reproducing the high-frequency oscillating cross sections. Recently, the applications of machine learning methods in nuclear physics have been expanding. In this paper, a novel Phase Shift Deep Neural Network (PSDNN) method, which not only overcomes the limitations of other machine learning methods in fitting the high-frequency oscillating data, but also is more concise than the R-matrix method, is developed to reproduce the neutron resonance cross sections. The results show that PSDNN method can simultaneously reproduce the low and high-frequency oscillating cross sections for the 235U(n , f) reaction with high accuracy and efficiency. Moreover, from an algorithmic point of view, the PSDNN method lays a solid foundation for further fine-grained processing of experimental data and extraction of critical neutron resonance parameters, opening up new possibilities for practical applications in nuclear data research. [ABSTRACT FROM AUTHOR]

Rare information on photodisintegration reactions of nuclei with mass numbers A ≈ 160 at astrophysical conditions impedes our understanding of the origin of p-nuclei. Experimental determination of the key (p, γ) cross sections has been playing an important role in verifying nuclear reaction models and providing rates of relevant (γ, p) reactions in the γ process. In this paper we report the first cross-section measurements of 160Dy(p, γ)161Ho and 161Dy(p, n)161Ho in the beam energy range of 3.4–7.0 MeV, partially covering the Gamow window. Such determinations are possible by using two targets with various isotopic fractions. The cross-section data can put a strong constraint on the nuclear level densities and gamma strength functions for A ≈ 160 in the Hauser–Feshbach statistical model. Furthermore, we find the best parameters for TALYS that reproduce the available A ∼ 160 data, 160Dy(p, γ)161Ho and 162Er(p, γ)163Tm, and recommend the constrained 161Ho(γ, p)160Dy reaction rates over a wide temperature range for γ process network calculations. Although the determined 161Ho(γ, p) stellar reaction rates at the temperature of 1 to 2 GK can differ by up to one order of magnitude from the NON-SMOKER predictions, it has a minor effect on the yields of 160Dy and accordingly the p-nuclei, 156,158Dy. A sensitivity study confirms that the cross section of 160Dy(p, γ)161Ho is measured precisely enough to predict yields of p nuclei in the γ process. [ABSTRACT FROM AUTHOR]